Radio stations may broadcast in different analog radio frequency domains. Audio signals may be transmitted through radio frequency (RF) waves, which may come from a transmission tower. If there is no interference, or the tower is not too far from a receiver (or tuner), audio frequencies may be presented to a user via an audio speaker. Audio signals may also be broadcast in a digital fashion. Digitally encoded media packets may be transmitted by radio frequency waves, which may come from a satellite. If there is no interference, packetized data may then be decoded, converted back to analog signals, and may be presented to a user via an audio speaker.
Radio stations may broadcast transmissions over a digital network. General-purpose computers have been adapted to take media streams from a digital network and present them to a user. In prior art embodiments of a digital network audio broadcast, the stream may be compressed on a server, sent to those general-purpose computers which are connected to that server on a digital network, data may be sent to a user general-purpose computer, uncompressed, converted into analog information, and may be presented to an audio speaker.
Downloading media streams to a general-purpose computer may be accomplished by connecting to a particular digital network address. Different media streams may come from different address on a digital network. In order to obtain information from a digital network, a general-purpose computer may communicate with digital network servers to connect properly to a specific digital network site.
FIG. 1 illustrates a Prior Art analog circuit (“radio”) which may be employed in typical radio frequency broadcast. Antenna 101 may receive radio waves from the air, and depending where tuner 106 is physically located, a particular frequency may be decoded and sent to amplifier 111 such that the information presently broadcast at that frequency may be audible over speaker 110. The frequency decoded by the position of the tuning mechanism may be user selectable by controllable knobs 102.
User interface logic 103 may then configure tuner 106. User interface logic 103 may be physically represented by a system of pulleys, gears, or other mechanical means, or by a digital tuner interface. User interface logic 103 may control analog storage 112 to record or play back broadcast radio audio streams. User interface logic 103 may control alarm 105 to notify the user when a specific time has been reached. Notification may be in the form of a fixed frequency audible tone, or enabling the output of tuner 106. User interface logic 103 may interact with time keeper 113 such that functions such as alarm 105 may be triggered at the correct user configurable time.
FIG. 2 illustrates a block diagram of a Prior Art general-purpose computer hardware. Circuits which represent mouse and keyboard interface logic and hardware 210, central processing unit 215, system memory 214, bus arbitration and memory arbitration logic 213, display controllers 208, display devices 207, and audio decoders 202 with speakers 206 are considered prior art and typical of computer designs.
The purpose of the hardware of the general-purpose computer of FIG. 2 in terms of audio play back may be enhanced by the addition of digital network interface card 200, which may be used to present media streams from a digital network. Central Processing Unit (CPU) 215 may be used to decode data received over system bus 216 from digital network interface card 200. Uncompressed digital representations of data may be sent to CRT/LCD controller 208 for presentation to the user on display device 207. Uncompressed digital representations of audio data may be sent by CPU 215 over system bus 216 to audio DAC/ADC 202 for presentation to the user on speaker 206.
The function of the general-purpose computer of FIG. 2 in terms of audio play back may be enhanced by the addition of specialized analog radio frequency tuner and decoder 201. Control software may communicate over system bus 216 to digitally 5 manipulate and tune a specialized analog radio frequency tuner and decoder 201. Analog audio input may be encoded by audio DAC/ADC 202 once received from microphone/input 217.
CPU 215 may also incorporate a method of keeping time. Synchronization of this method may be done by querying a time server connected to the digital network interface card 200. The time keeping method may also incorporate time events. These events may start play back of either a user selected digital information stream, locally stored information stream, broadcast radio, or locally stored analog media. The events may also trigger storage of user selected digital streams either simultaneously or sequentially, and/or broadcast radio.
FIG. 3 illustrates a block diagram of how software may execute on a general-purpose computer configured with digital network interface card 200 and specialized analog radio frequency tuner and decoder 201. FIG. 3 illustrates how a general-purpose computer may interact with a network and generalized server computer which provides media streams over a network, and how data may be sent from a general-purpose computer to be broadcast over a digital network. Control software 301 through 309 control various stages of how a user may enter keystrokes or click a mouse to enable a particular piece of a general-purpose computer to play analog and digital media streams.
The General-purpose computer described in FIG. 3 may also decode digitally encoded media packets which may be transmitted by radio frequency waves. In order to configure the system to play back this digital radio media stream, functional blocks may have a dual purpose. Radio frequency broadcast to analog transducer software control 307 may enable specialized radio frequency tuner and decoder 201 previous described in FIG. 2 to also decode media packets before sending it to audio DAC/ADC 202 for presentation to the user.
Broadcast radios described in FIG. 1 may not be connected to a digital network and may not have the capability to play back digital media streams from a digital network. Broadcast radio receivers may not have the capability of digitally broadcasting media streams over a digital network. Broadcast radio receivers may have the capability to record analog media to a storage device, such as a cassette tape. Broadcast radios receivers may not have the capability to record digital media from a digital network. This may render a broadcast radio receiver useless for gathering information from a digital network or sending it to a digital network.
General-purpose computers may play back digital media streams from a network or connection to a digital network. General-purpose computers may play back analog radio frequency signals much like an analog radio with a specialized computer card which digitally tunes frequencies. General-purpose computers may also decode digitally encoded media packets which may be transmitted by radio frequency waves. General-purpose computers may have media stream inputs which may be encoded and broadcast over a digital network.
General-purpose computers may have the ability to record media streams from a digital network or a radio frequency source. General-purpose computers may require a general-purpose user interface such as keyboard or mouse which may be used to configure analog radios with digital interfaces and digital network addresses for digital network media streams. General-purpose computers may be configured through a variety of software functions which may rely upon general-purpose user interfaces such as a keyboard or a mouse. General-purpose computers may have any one of these functions added by different manufacturers. Configuration and use may take multiple windows and user interactions to create the desired effect. General-purpose computers may not have an integrated control mechanism which may be manipulated for broadcast radio frequencies, digital network address tuning, volume control, recording enable, digital network broadcast enable, time event selection, secure transaction selection, user preference enable, and stream purchase/rental selection.